UserFilterCommand Class

Filters the image based on a user-defined filter / mask. This command is similar to the spatial and binary filter commands.

Object Model

Syntax

Visual Basic
C#
WinRT C#
WinRT JavaScript
C++

public class UserFilterCommand : Leadtools.ImageProcessing.RasterCommand, Leadtools.ImageProcessing.IRasterCommand

'Declaration
 
Public Class UserFilterCommand 
   Inherits Leadtools.ImageProcessing.RasterCommand
   Implements Leadtools.ImageProcessing.IRasterCommand

'Usage
 
Dim instance As UserFilterCommand

public sealed class UserFilterCommand : Leadtools.ImageProcessing.IRasterCommand

function Leadtools.ImageProcessing.Effects.UserFilterCommand()

public ref class UserFilterCommand : public Leadtools.ImageProcessing.RasterCommand, Leadtools.ImageProcessing.IRasterCommand

Remarks

With this command you can create a user-defined filter and apply it to the image. The filter has a rectangular form (matrix) where the values are user-defined. It allows the creation of simple customized filters, where each value in matrix is multiplied by the corresponding pixel, and then the specified operation is performed on the results.
When the filter is applied to pixels from the edge and you choose the sum operation, the edge rows and columns are duplicated. For example, if the pixel (-1, 5) is needed, the pixel (0, 5) is used instead.
This command supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale and 48 and 64-bit color images is available only in the Document/Medical toolkits.
This command does not support 32-bit grayscale images.

Example

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Public Sub UserFilterCommandExample()
   Dim codecs As New RasterCodecs()
   codecs.ThrowExceptionsOnInvalidImages = True

   Dim leadImage As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Master.jpg"))

   ' Prepare the command
   Dim i As Integer
   Dim j As Integer
   Dim matrix() As Integer
   ReDim matrix(8)

   Dim command As UserFilterCommand = New UserFilterCommand
   command.CenterPoint = New LeadPoint(1, 1)
   command.Divisor = 1
   command.Offset = 0
   command.Type = UserFilterCommandType.Sum
   command.FilterHeight = 3
   command.FilterWidth = 3
   command.Matrix = matrix

   ' Initialize the array with factor used to apply the high pass filter.
   For i = 0 To 2
      For j = 0 To 2
         If (j = 1 Or i = 1) Then
            If (j = 1 And i = 1) Then
               command.Matrix(i * 3 + j) = 5
            Else
               command.Matrix(i * 3 + j) = -1
            End If
         Else
            command.Matrix(i * 3 + j) = 0
         End If
      Next
   Next

   ' Apply the high pass custom filter.
   command.Run(leadImage)
   codecs.Save(leadImage, Path.Combine(LEAD_VARS.ImagesDir, "Result.jpg"), RasterImageFormat.Jpeg, 24)

End Sub

Public NotInheritable Class LEAD_VARS
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class

public void UserFilterCommandExample()
   {
      // Load an image
      RasterCodecs codecs = new RasterCodecs();
      codecs.ThrowExceptionsOnInvalidImages = true;

      RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Master.jpg"));

      // Prepare the command
      int i, j;
      UserFilterCommand command = new UserFilterCommand();
      command.CenterPoint = new LeadPoint(1, 1);
      command.Divisor = 1;
      command.Offset = 0;
      command.Type = UserFilterCommandType.Sum;
      command.FilterHeight = 3;
      command.FilterWidth = 3;
      command.Matrix = new int[9];

      // Initialize the array with factor used to apply the high pass filter.
      for(i = 0; i < 3; i++)
      {
         for(j = 0; j < 3; j++)
         {
            if(j == 1 || i == 1) 
            {
               if(j == 1 && i == 1) 
                  command.Matrix[i * 3 + j] = 5; 
               else 
                  command.Matrix[i * 3 + j] = -1; 
            }
            else
               command.Matrix[i * 3 + j] = 0; 
         }
      }

      // Apply the high pass custom filter.
      command.Run(image);

   }

static class LEAD_VARS
{
   public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}

[TestMethod]
public async Task UserFilterCommandExample()
{
   // Load an image
   RasterCodecs codecs = new RasterCodecs();
   codecs.ThrowExceptionsOnInvalidImages = true;
   // Load the image
   string srcFileName = @"Assets\Image1.cmp";
   StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName);
   RasterImage image = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile));


   // Prepare the command
   int i, j;
   UserFilterCommand command = new UserFilterCommand();
   command.CenterPoint = LeadPointHelper.Create(1, 1);
   command.Divisor = 1;
   command.Offset = 0;
   command.Type = UserFilterCommandType.Sum;
   command.FilterHeight = 3;
   command.FilterWidth = 3;
   command.Matrix = new int[9];

   // Initialize the array with factor used to apply the high pass filter.
   for(i = 0; i < 3; i++)
   {
      for(j = 0; j < 3; j++)
      {
         if(j == 1 || i == 1) 
         {
            if(j == 1 && i == 1) 
               command.Matrix[i * 3 + j] = 5; 
            else 
               command.Matrix[i * 3 + j] = -1; 
         }
         else
            command.Matrix[i * 3 + j] = 0; 
      }
   }

   // Apply the high pass custom filter.
   command.Run(image);

}

public void UserFilterCommandExample(RasterImage image, Stream outStream)
{
   // Prepare the command
   int i, j;
   UserFilterCommand command = new UserFilterCommand();
   command.CenterPoint = new LeadPoint(1, 1);
   command.Divisor = 1;
   command.Offset = 0;
   command.Type = UserFilterCommandType.Sum;
   command.FilterHeight = 3;
   command.FilterWidth = 3;
   command.Matrix = new int[9];
   // Initialize the array with factor used to apply the high pass filter.
   for (i = 0; i < 3; i++)
   {
      for (j = 0; j < 3; j++)
      {
         if (j == 1 || i == 1)
         {
            if (j == 1 && i == 1)
               command.Matrix[i * 3 + j] = 5;
            else
               command.Matrix[i * 3 + j] = -1;
         }
         else
            command.Matrix[i * 3 + j] = 0;
      }
   }

   // Apply the high pass custom filter.
   command.Run(image);
   // Save result image
   RasterCodecs codecs = new RasterCodecs();
   codecs.Save(image, outStream, RasterImageFormat.Jpeg, 24);
   image.Dispose();
}

Public Sub UserFilterCommandExample(ByVal image As RasterImage, ByVal outStream As Stream)
   ' Prepare the command
   Dim i, j As Integer
   Dim command As UserFilterCommand = New UserFilterCommand()
   command.CenterPoint = New LeadPoint(1, 1)
   command.Divisor = 1
   command.Offset = 0
   command.Type = UserFilterCommandType.Sum
   command.FilterHeight = 3
   command.FilterWidth = 3
   command.Matrix = New Integer(8){}
   ' Initialize the array with factor used to apply the high pass filter.
   For i = 0 To 2
      For j = 0 To 2
         If j = 1 OrElse i = 1 Then
            If j = 1 AndAlso i = 1 Then
               command.Matrix(i * 3 + j) = 5
            Else
               command.Matrix(i * 3 + j) = -1
            End If
         Else
            command.Matrix(i * 3 + j) = 0
         End If
      Next j
   Next i

   ' Apply the high pass custom filter.
   command.Run(image)
   ' Save result image
   Dim codecs As RasterCodecs = New RasterCodecs()
   codecs.Save(image, outStream, RasterImageFormat.Jpeg, 24)
   image.Dispose()
End Sub

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference